It is well known to those skilled in the art to utilize a finely focused laser beam to cut various materials both organic and inorganic, which have found widespread commercial use. It is further known to utilize such devices to etch or scribe multi-layer constructions comprising laminae, of for example, an inorganic support or substrate bearing a metallic layer thereon, wherein the metallic layer is selectively removed by the laser. However, when it is desirable to provide a complex pattern such as, for example, an array of closely spaced metallic stripes on a dielectric support, known laser scribing techniques are unsatisfactory because of the excessive time required to accomplish scribing, and because of the complex and costly apparatus necessary to precisely position and scan the laser when utilizing a single source of laser radiation.
It has been proposed to utilize lenticular lens arrays in the form of thin sheets to concentrate solar energy as disclosed by Baker in U.S. Pat. No. 4,456,783 and Adcock in U.S. Pat. No. 4,446,853. U.S. Pat. No. 4,456,783 describes a thin optical panel formed of two, preferably identical, but opposed, spaced lenticulated plates structured to form a series of regularly spaced apart line images of the sun with the line images thus formed being tracked with an array of silicon ribbons or the like to convert solar energy to electrical energy.
U.S. Pat. No. 4,306,278 discloses a semiconductor laser array system including a plano-cylindrical inner lens of relatively short focal length for each row of laser elements. In such an array, the flat surface of the lens adjacent the laser radiation emitting source and a second single plano-cylindrical lens are combined with the rows of inner lenses to yield an assembly providing essentially complete culmination (as opposed to focusing to a fine line) of the laser radiation.
U.S. Pat. No. 3,600,063 by Bowen discloses a varifocal beam spreader positioned in the path of a light beam (especially a laser) for varying the light beam divergence angle while maintaining a uniform intensity of illumination. The spreader includes a lenticular plate comprising a series of elongated lenslets forming a series of parallel semicircular tubes. The radiation source is, as in U.S. Pat. No. 4,306,278, incident on the flat surface of the lenticular plate, and the apparatus does not provide for focusing of the radiation to fine lines.